//
//  Array+UITableDataSource.swift
//  TournamentStats
//
//  Created by Laurent Morvillier on 05/08/2019.
//  Copyright © 2019 Stax River. All rights reserved.
//

import Foundation
import UIKit

class DataSourceWrapper<T : ColumnRepresentable> : NSObject, UITableViewDataSource, UITableViewDelegate {

    var columnRepresentables: [T]
    var columnDescriptors: [ColumnDescriptor] // = T.columnDescriptors()
    var totalWidthWeigth: CGFloat = 0.0
    fileprivate var _maxRows: Int?

    init(array: [T], maxRows: Int? = nil) {
        self.columnRepresentables = array
        self.columnDescriptors = array.first?.columnDescriptors() ?? []
        self.totalWidthWeigth = self.columnDescriptors.map { $0.widthWeight }.reduce(0, +)
        if let max = maxRows, max > columnRepresentables.count {
            self._maxRows = nil
        } else {
            self._maxRows = maxRows
        }
    }
    
    func tableView(_ tableView: UITableView, numberOfRowsInSection section: Int) -> Int {
//        print("numberOfRowsInSection = \(self.columnRepresentables.count)")
        if let max = self._maxRows {
            return 1 + max
        } else {
            return self.columnRepresentables.count + 1 // + 1 for header
        }
    }
    
    fileprivate let FONTSIZE: CGFloat = 18.0
    
    func tableView(_ tableView: UITableView, cellForRowAt indexPath: IndexPath) -> UITableViewCell {
//        let cell = tableView.dequeueReusableCell(withIdentifier: "Cell") as! StackTableCell
        let cell = UITableViewCell()
        cell.backgroundColor = UIColor.clear

        var cells: [String]
        switch indexPath.row {
        case 0:
            cells = columnDescriptors.map { $0.header }
        default:
            let cr = self.columnRepresentables[indexPath.row - 1]
            cells = cr.cellValues()
        }
        
        var font: UIFont = Fonts.bold
        
        var leftAnchor = cell.contentView.leftAnchor
        for (index, value) in cells.enumerated() {

            if (indexPath.row > 0) {
                font = self.columnDescriptors[index].number ? Fonts.monospaced : Fonts.regular
            }
            
            let labelContainer: UIView = UIView()
            cell.contentView.addSubview(labelContainer)
            labelContainer.translatesAutoresizingMaskIntoConstraints = false
            labelContainer.topAnchor.constraint(equalTo: cell.contentView.topAnchor).isActive = true
            labelContainer.bottomAnchor.constraint(equalTo: cell.contentView.bottomAnchor).isActive = true
            let leftPadding: CGFloat = (index == 0) ? 0.0 : 0.0 //16.0
            labelContainer.leftAnchor.constraint(equalTo: leftAnchor, constant: leftPadding).isActive = true
            leftAnchor = labelContainer.rightAnchor

//            labelContainer.backgroundColor = index.isMultiple(of: 2) ? UIColor.clear : UIColor(white: 0.9, alpha: 0.1)
            labelContainer.backgroundColor = UIColor.clear
            
            let multiplier: CGFloat = self.columnDescriptors[index].widthWeight / self.totalWidthWeigth
            labelContainer.widthAnchor.constraint(equalTo: cell.contentView.widthAnchor, multiplier: multiplier).isActive = true

            let label: UILabel = UILabel(frame: CGRect.zero)
            label.textColor = UIColor.white
            label.backgroundColor = UIColor.clear
            label.text = value
            label.font = font
            label.textAlignment = self.columnDescriptors[index].number ? .right : .left
            labelContainer.addSubview(label)

            label.translatesAutoresizingMaskIntoConstraints = false
            label.topAnchor.constraint(equalTo: labelContainer.topAnchor).isActive = true
            label.bottomAnchor.constraint(equalTo: labelContainer.bottomAnchor).isActive = true
            label.leftAnchor.constraint(equalTo: labelContainer.leftAnchor, constant: 8.0).isActive = true
            label.rightAnchor.constraint(equalTo: labelContainer.rightAnchor, constant: -8.0).isActive = true

        }
        return cell
    }
    
    func tableView(_ tableView: UITableView, heightForRowAt indexPath: IndexPath) -> CGFloat {
        return 36.0
    }
    
    func tableView(_ tableView: UITableView, heightForHeaderInSection section: Int) -> CGFloat {
        return 0.1
    }

}